Study Questions:

What is the association between alcohol consumption and outcomes in countries at different economic levels in five continents?

Methods:

Information was collected from 12 countries participating in the PURE (Prospective Urban Rural Epidemiological) study, a prospective cohort study of individuals ages 35-70 years. Cox proportional hazards regression was used to study associations with mortality (n = 2,723), cardiovascular disease (n = 2,742), myocardial infarction (n = 979), stroke (n = 817), alcohol-related cancer (n = 764), injury (n = 824), admission to hospital (n = 8,786), and for a composite of these outcomes (n = 11,963). Among current alcohol consumers, low intake was defined as up to seven drinks per week, moderate intake was defined as 7–14 drinks per week for women or 7–21 drinks per week for men, and high intake was defined as more than 14 drinks per week for women or more than 21 drinks per week for men.

Results:

There were 114,970 adults without baseline history of heart disease, stroke, or cancer, of whom 11% were from high-income countries (HICs), 21% were from upper-middle-income countries (UMICs), 43% were from lower-middle-income countries (LMICs), and 25% were from low-income countries (LICs). Median follow-up was 4.3 years (interquartile range, 3.0–6.0). About 75% of HICs and 12% of LICs consumed alcohol. Current drinking was reported by 36,030 (31%) individuals, and was associated with reduced myocardial infarction (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.63–0.93), but increased alcohol-related cancers (HR, 1.51; 95% CI, 1.22–1.89) and injury (HR, 1.29; 95% CI, 1.04–1.61). High intake was associated with increased mortality (HR, 1.31; 95% CI, 1.04–1.66). Compared with never drinkers, there was a signiﬁcantly reduced hazard for the composite outcome for current drinkers in HICs and UMICs (HR, 0.84; 95% CI, 0.77–0.92), but not in LMICs and LICs, for which there were no reductions in this outcome (HR, 1.07; 95% CI, 0.95–1.21; pinteraction < 0.0001).

Conclusions:

Current alcohol consumption had differing associations by clinical outcome, and differing associations by income region. However, there are sufficient commonalities to support global health strategies and national initiatives to reduce harmful alcohol use.

Perspective:

The findings add to the literature on excessive alcohol consumption and overall mortality in relationship to low socioeconomic status. However, the results are not generalizable in relationship to low to moderate alcohol consumption, as defined in the study.